I'm late! I Had the same thing on a mustang and I had the calipers on the wrong sides,It drove me nuts till I figured it out. When you look at a ford caliper it looks correct but it is not. Glad it worked out Russ
When some one has a problem they need help with they should post more pictures !!! Its kinda hard to fix a car you cant see ... If we had have had pictures of the caliper we could have seen it was up side down bleeders on the bottom ... Same with the guys choke ,,, we could have seen right away the choke was closed ... OK from now on More Pictures for Me ...
Thanks for letting us know what you found. So many times the original poster just leaves us hanging. Hopefully someone with the same problem will find this in a search and solve their own problem.
Below are some pictures of master cylinders designed for vacuum power boosters. (The lighting isn't the best) They range from a '68 F-250, '70 Mustang, and 2 from '80s-'90s Ford products. They all have push rod bores around 1.4" deep, or about the length of the full stroke of each master. I don't remember ever seeing or working with a power master that didn't have deep push rod bores, but there may have been one or two. Some boosters may have a guided push rod that would work with a shallow bore master, but most/all the ones I have worked with need the push rod to be captured safely into the master cylinder. I refer mainly to '60s-80s designs, where power brakes were still an option on several cars. By the late '80s manual brakes in the US were all but obsolete. I don't know what the masters are in your picture, or how you know anything about them, but if they are what you state, then the best thing to do when buying a master cylinder for a custom application is to compare power and non-power examples and use the one with the deeper push rod bore. I know the popular Mustang and similar Bendix power masters all have deep bores. As for your at***ude toward me and others, It ****s! Brake safety is one of my main topics of concern because of mis-information and lack of basic brake knowledge. Good ole boy education? Real nice. I spent most of my working years making sure vehicle brake systems are safe, and don't appreciate your insensitive, stupid, clueless comments. You're right-respect IS earned, and you've got a hell of a long way to get any from me and some others.
And Iam damn sure one of the others !!! With a at***ude like he has respect will be the last thing he gets and he will find that out the hard way ...
Thanks v-8 Bob, as just another unedjucated shade tree mechanic, I know what I know and I don't know what I don't know.
All good things,...Definitely look into the residual check valves,...be sure ther is a 10 lb unit for the rear (drum) brakes. MUST use a m/cy that has the deep pushrod hole !!!!!!!!!!!!!!!! 4TTRUK
Do you need a residual valve for the front discs? I know Speedway recommends 2lb for the front. Every now and then my left front hangs and I wonder what causes it. Did it at the HAMB drags last year and still managed to go 13. Sure smelled bad when I turned up the return road with the wind in my face.
The only time modern disc brakes may need a residual is when the master cylinder is located lower than the calipers, and then only an aftermarket inline 2 lb valve.
Thanks for the info V8 Bob, My M/C is on the frame close to level with the calipers. I installed a 2lb valve based on the Speedway recommendation but never knew if I really needed to. Seems to work good except as I stated before about it hanging up sometimes. Only happened a couple times in 10 years. I thinks its the caliper causing this.
The question of whether a 2 lb residual valve is really necessary for discs when the master is lower than the calipers is a very good one, because I don't know for sure. There was never a production US vehicle that used modern disc brakes car with the master cylinder frame mounted, so there is no history of any fluid drain-back problems that I've ever seen or know of. The idea of any check valve in a disc brake circuit made me think twice about installing one on my '32 with a floor mounted master, but I figured it could easily be removed if a problem developed. To date I've had no issues of brake drag with a 2 lb valve going to the 4 piston Wilwood calipers, so some thought and/or testing went into the manufacture and recommendation of 2 lb valves with disc brakes and floor mounted masters. I agree with you that you may have a bad caliper, but also make sure the pedal is returning fully and with it's own spring. Do not rely on the master cylinder to return the pedal. You should have 1/16" or so push rod free play when the pedal is fully returned.
I built my first 34 in the very early 80s long before the internet and the specialized brake suppliers for the hobby. I used everything from a 71 Camaro... dual M/cyl, distribution block , calipers and the Camaro rear. Only the lines were changed to fit the truck. The M/cyl was mounted on the frame with a Pete and Jake under the floor pedal mount. I had no aftermarket residual check valves at all, just the one inside the M/cyl for the rear brakes. I never had any problems at all. No "drain back". It's OMO but I don't believe in aftermarket residual valves for the front. I've read about people having problems with some of the aftermarket valves. I've never found it necessary to run one. Just my personal experience.
Got it solved and it wasn't the mc. I have Wilwood calipers on the front and they are mounted at the top with 2 front and 2 rear bleeders on each side of the caliper. Being mounted like that, all the air collected on the top and wasn't getting bled out. I temporarily moved the calipers to the rear mounting hole and front hole on the caliper with it hanging down the back side of the rotor making the bleeder on the top and bled both sides like that then mounted them back like they were and I have a very good pedal, and solid.
The Jalopy Journal
